# -*- coding: UTF-8 -*-
from typing import List
from leetcode_helper import TestcaseHelper, SolutionBase


class Solution(SolutionBase):
    # 解题的方法，命名和Leetcode的保持一致即可
    def permute(self, nums: List[int]) -> List[List[int]]:
        result = []

        def backtrace(items: List[int], track: List[int]):
            if len(track) == len(items):
                result.append(track.copy())
                return

            for item in items:
                if item in track:
                    continue
                track.append(item)
                backtrace(items, track)
                track.pop()

        backtrace(nums, [])
        return result


if __name__ == '__main__':
    solution = Solution()

    # 按照leetcode的题目说明，将基本的test case填入
    # 每条case的最后一个元素是正确的结果，即期待的结果
    # 使用元组来保存输入的数据，期待的结果
    testcases = [
        ([1, 2, 3], [[1, 2, 3], [1, 3, 2], [2, 1, 3], [2, 3, 1], [3, 1, 2], [3, 2, 1]]),
        ([0, 1], [[0, 1], [1, 0]]),
        ([1], [[1]])
    ]

    for case_item in testcases:
        # 获取测试用的case和期待的执行结果
        input1 = case_item[0]
        expect = case_item[len(case_item) - 1]
        exec_result = solution.permute(input1)

        # 判断执行结果，输出提示信息
        check_result = solution.check_result(expect, exec_result)
        TestcaseHelper.print_case(check_result, case_item, exec_result)

